软土地基上高层隔震结构模型振动台试验研究
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摘要
通过对高层隔震结构模型在刚性地基和软土地基条件下进行对比振动台试验,研究软土地基上高层隔震结构的地震反应特性和隔震效果。采用叠层剪切型土箱以减小边界影响,采用粉质黏土作为模型土,考虑基底压力的相似,采用高宽比为4的5层钢框架作为上部隔震结构模型,设计了软土地基上高层隔震结构、非隔震结构以及刚性地基上隔震、非隔震结构的振动台试验模型。试验结果表明:土-结构相互作用(SSI)效应对隔震结构的影响程度较非隔震结构轻;SSI效应显著降低了隔震结构模型的自振频率、增加了体系的阻尼;软土地基上隔震结构能够有效减轻结构的地震反应,但是相对于非隔震结构的加速度反应比值增大,隔震效果降低;SSI效应可能增加也可能减小隔震结构的地震反应,不仅与地震动类型有关还与输入地震动强度相关;软土地基上高层隔震结构基础输入地震动与自由场地震动在反应谱水平上基本一致,采用自由场地震动确定基础输入地震动是可行的,且偏于安全,而非隔震结构基础输入地震动则与地基更深层的地震动接近。
In order to investigate the seismic behavior and isolation effectiveness of a high-rise isolated structure on soft soil foundation,the shaking table tests of a high-rise isolated model on rigid and soft soil foundation were conducted.A laminar shear soil container was fabricated to minimize the boundary effects.With the similitude of the soil pressure,five-story steel frame models of aspect ratio 4,either with or without rubber bearings,supported by a pile group,and seated on a silty clay deposit,were subjected to different strong ground motions.From the results,it is found that soil-structure interaction(SSI) effects on high-rise isolated structure models are not as important as those in unisolated counterpart.Due to SSI,the natural frequency of the isolated model system is obviously reduced,and damping ratio largely increased.The efficiency of the presented isolation system on soft soil is confirmed.However,the ratio of peak acceleration of the isolated model to the unisolated one on soft soil is increased,with the isolation effectiveness reduced relatively.SSI can increase or decrease the seismic response of high-rise isolated model,depending on not only the type but also the intensity of the earthquake motion.It is also observed that the acceleration response spectrum of the foundation input motion agrees well with that of the free-field motion for the isolated structure.While,for the unisolated one,it is close to those of the ground motions at greater depths of soil.
In order to investigate the seismic behavior and isolation effectiveness of a high-rise isolated structure on soft soil foundation,the shaking table tests of a high-rise isolated model on rigid and soft soil foundation were conducted.A laminar shear soil container was fabricated to minimize the boundary effects.With the similitude of the soil pressure,five-story steel frame models of aspect ratio 4,either with or without rubber bearings,supported by a pile group,and seated on a silty clay deposit,were subjected to different strong ground motions.From the results,it is found that soil-structure interaction(SSI) effects on high-rise isolated structure models are not as important as those in unisolated counterpart.Due to SSI,the natural frequency of the isolated model system is obviously reduced,and damping ratio largely increased.The efficiency of the presented isolation system on soft soil is confirmed.However,the ratio of peak acceleration of the isolated model to the unisolated one on soft soil is increased,with the isolation effectiveness reduced relatively.SSI can increase or decrease the seismic response of high-rise isolated model,depending on not only the type but also the intensity of the earthquake motion.It is also observed that the acceleration response spectrum of the foundation input motion agrees well with that of the free-field motion for the isolated structure.While,for the unisolated one,it is close to those of the ground motions at greater depths of soil.
引文
[1]Higashino Masahiko,Okamoto Shin.Response controland seismic isolation of buildings[M].London/NewYork:Taylor&Francis,2006:63-86.
[2]日本建筑学会.隔震结构设计[M].刘文光,译.北京:地震出版社,2006:110-140.(ArchitecturalInstitute of Japan.Recommendation for the design ofbase isolated buildings[M].Translated by LiuWenguang.Beijing:Seismological Press,2006:110-140.(in Chinese))
[3]Constantinou M C,Kneifati C.Dynamics of soil-base-isolated-structure system[J].Journal of StructuralEngineering,ASCE,1988,144(1):211-220.
[4]李海岭,葛修润.土-结构相互作用对基础隔震体系的影响[J].土木工程学报,2001,34(4):83-87.(Li Hailing,Ge Xiurun.Effect of soil-structureinteraction on base-isolated building system[J].ChinaCivil Engineering Journal,2001,34(4):83-87.(inChinese))
[5]Tsai C S,Chen C S,Chen B J.Effects of unboundedmedia on seismic responses of FPS-isolated structures[J].Structural Control and Health Monitoring,2004,11(1):1-20.
[6]Spyrakos C C,Koutromanos I A,Maniatakis Ch A.Seismic response of base-isolated buildings includingsoil-structure interaction[J].Soil Dynamics andEarthquake Engineering,2009,29(4):658-668.
[7]吕西林,陈跃庆,陈波,等.结构-地基动力相互作用体系振动台模型试验研究[J].地震工程与工程振动,2000,20(4):20-29.(Lu Xilin,ChenYueqing,Chen Bo,et al.Shaking table testing ofdynamic soil-structure interaction system[J].Earthquake Engineering and Engineering Vibration,2000,20(4):20-29.(in Chinese))
[8]李培振,程磊,吕西林,等.可液化土-高层结构地震相互作用振动台试验[J].同济大学学报,2010,38(4):467-474.(Li Peizhen,Cheng Lei,Lu Xilin,et al.Shaking table testing on high-rise buildingsconsidering liquefiable soil-structure interaction[J].Journal of Tongji University,2010,38(4):467-474.(in Chinese))
[9]姜忻良,李岳.土-桩-偏心结构相互作用体系振动台试验研究[J].建筑结构学报,2010,31(8):106-111.(JIANG Xinliang,LI Yue.Shaking table test ofsoil-pile-eccentric structure interaction system[J].Journal of Building Structures,2010,31(8):106-111.(in Chinese))
[10]宋二祥,武思宇,王宗纲.地基-结构系统振动台模型试验中相似比的实现问题探讨[J].土木工程学报,2008,41(10):87-92.(Song Erxiang,Wu Siyu,Wang Zonggang.A tentative solution for similituderrealization in shaking table tests of SSI systems[J].China Civil Engineering Journal,2008,41(10):87-92.(in Chinese))
[11]陈国兴,王志华,左熹,等.振动台试验叠层剪切型土箱的研制[J].岩土工程学报,2010,31(1):89-96.(Chen Guoxing,Wang Zhihua,Zuo Xi,et al.Development of laminar shear soil container for shakingtable tests[J].Chinese Journal of GeotechnicalEngineering,2010,31(1):89-96.(in Chinese))
[12]Finn W D Liam,Gohl W Blair.Response of model pilegroups to strong shaking[C]//Prakash S.Piles UnderDynamic Loads.Geotechnical Special Publication,No.34.Reston,VA:ASCE,1992:27-55.
[2]日本建筑学会.隔震结构设计[M].刘文光,译.北京:地震出版社,2006:110-140.(ArchitecturalInstitute of Japan.Recommendation for the design ofbase isolated buildings[M].Translated by LiuWenguang.Beijing:Seismological Press,2006:110-140.(in Chinese))
[3]Constantinou M C,Kneifati C.Dynamics of soil-base-isolated-structure system[J].Journal of StructuralEngineering,ASCE,1988,144(1):211-220.
[4]李海岭,葛修润.土-结构相互作用对基础隔震体系的影响[J].土木工程学报,2001,34(4):83-87.(Li Hailing,Ge Xiurun.Effect of soil-structureinteraction on base-isolated building system[J].ChinaCivil Engineering Journal,2001,34(4):83-87.(inChinese))
[5]Tsai C S,Chen C S,Chen B J.Effects of unboundedmedia on seismic responses of FPS-isolated structures[J].Structural Control and Health Monitoring,2004,11(1):1-20.
[6]Spyrakos C C,Koutromanos I A,Maniatakis Ch A.Seismic response of base-isolated buildings includingsoil-structure interaction[J].Soil Dynamics andEarthquake Engineering,2009,29(4):658-668.
[7]吕西林,陈跃庆,陈波,等.结构-地基动力相互作用体系振动台模型试验研究[J].地震工程与工程振动,2000,20(4):20-29.(Lu Xilin,ChenYueqing,Chen Bo,et al.Shaking table testing ofdynamic soil-structure interaction system[J].Earthquake Engineering and Engineering Vibration,2000,20(4):20-29.(in Chinese))
[8]李培振,程磊,吕西林,等.可液化土-高层结构地震相互作用振动台试验[J].同济大学学报,2010,38(4):467-474.(Li Peizhen,Cheng Lei,Lu Xilin,et al.Shaking table testing on high-rise buildingsconsidering liquefiable soil-structure interaction[J].Journal of Tongji University,2010,38(4):467-474.(in Chinese))
[9]姜忻良,李岳.土-桩-偏心结构相互作用体系振动台试验研究[J].建筑结构学报,2010,31(8):106-111.(JIANG Xinliang,LI Yue.Shaking table test ofsoil-pile-eccentric structure interaction system[J].Journal of Building Structures,2010,31(8):106-111.(in Chinese))
[10]宋二祥,武思宇,王宗纲.地基-结构系统振动台模型试验中相似比的实现问题探讨[J].土木工程学报,2008,41(10):87-92.(Song Erxiang,Wu Siyu,Wang Zonggang.A tentative solution for similituderrealization in shaking table tests of SSI systems[J].China Civil Engineering Journal,2008,41(10):87-92.(in Chinese))
[11]陈国兴,王志华,左熹,等.振动台试验叠层剪切型土箱的研制[J].岩土工程学报,2010,31(1):89-96.(Chen Guoxing,Wang Zhihua,Zuo Xi,et al.Development of laminar shear soil container for shakingtable tests[J].Chinese Journal of GeotechnicalEngineering,2010,31(1):89-96.(in Chinese))
[12]Finn W D Liam,Gohl W Blair.Response of model pilegroups to strong shaking[C]//Prakash S.Piles UnderDynamic Loads.Geotechnical Special Publication,No.34.Reston,VA:ASCE,1992:27-55.
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